[Error] Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in

<?php
@mysql_connect("localhost", "root", "admin") or die("Not Connected");
@mysql_select_db("fuku2nd") or die("Not Correct"); 
function paging_start_row($current_page,$rows_per_page){
}
function paging_total_pages($total_rows, $rows_per_page){
}
function paging_pagenum($current_page,$total_pages,$page_range,$query_string){
}
$current_page = 1;
if(isset($_GET['page'])){
}
$rows_per_page = 5;
$start_row = paging_start_row($current_page, $rows_per_page);
$sql = "SELECT SQL_CALC_FOUND_ROWS 8 FROM product
LIMIT $start_row, $rows_per_page;";

$result = mysql_query($sql);
$found_rows = mysql_query ("SELECT FOUND_ROWS();");
$total_rows = mysql_result($found_rows,0,0);

if ($total_rows == 0){
	echo "<caption><b>ไม่พบสินค้า</b></caption>";
}
else {
	$stop_row = paging_stop_row($start_row,$rows_per_page,$total_rows);
	echo"<caption><b>รายการสินค้าลำดับที่: ".($start_row + 1).
	" - " . "$stop_row จากทั้งหมด $total_rows</b></caption>";
}
while($p = mysql_fetch_array($result)) {
	$id = $p['pro_id'];
	$descr = substr ($p['description'] , 0 , 80)  . " . . . " ;
	echo "
	<tr valign=top>
	<td rowspan=2 width=60 align=center>
	<img width=50 src=read_image.php?id=$id/>
	</td>
	<td colspan=2>
	<a href=product_detail.php?id=$id>
	<b>{$p['pro_name']}</b></a><br/>
	$descr
	</td>
	</tr>
	<tr valign=bottom>
	<td>
	ราคา : {$p['price']} บาท
	</td>
	<td align=right>
	<input type=button value=หยิบใส่รถเข็น class=add_cart
	onclick=\"addCart($id)\"/>
	</td>
	</tr>
	<tr><td colspan=3 class=line_dot>&nbsp;</td></tr>";
}
?>

	</table>
    <p align="center">
    <?php
	$page_range= 5;
	$qry_str="";
	$total_pages = paging_total_pages($total_rows,$rows_per_page);
	$pagenum = paging_pagenum($current_page, $total_pages, $page_range, $qry_str);
	echo "หน้า: " .$pagenum
	?>
    </td>
    <td width="261" bgcolor="#CCCCCC" id="cart">
    <script> readCart();</script>
    </td>
  </tr>
</table>
</body>